Just move into a new house that was built 5 months ago. I notice a sewer type smell outside. This smell comes and goes and is pretty stinky. the smell is outside by the septic system however it appears to be stronger on the deck which is over the septic tank. There are no wet spots on the ground I also notice a strong smell by the vent pipe when i was hanging xmas ligts. the house does not have a carbon filter on the vent pipe.

Does carbon filters work?Do sewer gases rise or fall? Any other suggestions?